Our magnetic supension balance techniques have been incorporated into the magnetic suspension viso-densimeter in which densities and viscosities are measured simultaneously with an accuracy of one part in 10 to the minus 5th power, and one part in 10 to the minus 3rd power to 10 to the minus 4th power respectively. The measurements are made on small batch samples (approximately 2 ml of solution) or while the solution is flowing continuously through the instrument. The above techniques also have been applied to the development of an osmometer which potentially can measure osmotic pressures of 10 to the minus 5th power cm water. The development of the above instruments will be continued in order to further increase their accuracy and speed. The present planned measurement of viscosities, densities and osmotic pressures of solutions of bio-macromolecular species as a function of concentration, pH, temperature (1 degrees to 30 degrees C) and pressure (1 to 1000 atmospheres) will be continued. These data are needed for the proper interpretation of ultracentrifugal data. The current simultaneous measurements of density and viscosity of solution undergoing physical and chemical changes will be extended. The solid like behavior at very low shearing stresses of TYMV solutions while excluding their RNA discovered in the above work will be investigated in depth. Dr. D. W. Kupke is a close collaborator in this work. BIBLIOGRAPHIC REFERENCES: "Solid Like Character of Virus Solutions", D. W. Kupke and J. W. Beams, Proc. Natl. Acad. Sci. 74, 1993 (1977). "Rigidity of Virus Solutions by Thin Fiber Technique", D. W. Kupke and J. W. Beams, Federation Proceedings 35, 1458 (1976).